Off-types so far (2010)

[Tania]

Originally Posted by stormymater

50% Cc & 50%cc from Cc x cc

Interestingly isn't the PL in the RL how KBX came into being?
I surely love my KBX!

I am not a biologist, so that where I probably always get confused - as I thought that in F1 generation all the plants are supposed to be the same, and not 50/50...

Wouldn't all the F1 plants still be RL in this case?

I guess I'll need more 101 on genetics

My apologies for the dummy questions!

Tania

[Gobig_or_Gohome_toms]

The 50/50 split would be the F2 generation plants, F1's would all have the same leaf type.

Originally Posted by Tania

I am not a biologist, so that where I probably always get confused - as I thought that in F1 generation all the plants are supposed to be the same, and not 50/50...

Wouldn't all the F1 plants still be RL in this case?

I guess I'll need more 101 on genetics

My apologies for the dummy questions!

Tania

[carolyn137]

Originally Posted by Tania

Carolyn,

So what happens when a 'Cc' tomato crosses with a 'cc' tomato?

Tania

Tania, this is what you asked so that's why Stormy answered and I also agreed and actually did the genetic square to share with you how the C and c genes combine, from two different plants so that you can get different leaf forms.

And yes, when you get an offtype leaf form it can be due to either a spontaneous mutation or a more compliceted mechanism and yes, the offtype plant can be a hybrid from the crossing of two different varieties.

But there can also be an offtype leaf form without any crossing at all if it's a single spontaneous mutation that occurs in the DNA of a single seed and when that seed is sowed, the variety is the same with a different leaf type.

Getting back to crossing now, the leaf type of the accidental hybrid will show the leaf type of the parent plant that had the dominant gene, the C gene.

And your question was a perfectly reasonable one in asking what happens if a Cc crosses with a cc? And since none of us really know if a specific RL variety has a CC genotype or a Cc genotype, we can only predict the possibilities.

Saved F1 seeds, now the F2, from fruits of an accidental cross can give you:

cc X cc will always give you PL if two PL varieties cross.
CC X CC will always give you RL if two CC varieties cross.
Cc X Cc will give give you 3/4 PL and 1/4 RL
CC X cc will give you all RL plants
CC X Cc will give you 1/2 RL and 1/2 PL

it's no different than saving F2 seeds from a deliberately bred F1 variety such as the many known commercial varieties or ones that many now days are doing in the back Yard.

My friend Steve Draper crossed Black Krim ( RL) with Galina's Yellow (PL) and sent me 4 F1 seeds. While I didn't need to I sowed all 4 seeds and got 4 plants that were identical. All were RL and the fruits were all a dusky reddish color and intermediate in size between the fruit sizes of both parents. I described the results in the thread here about crossing Snow White X Galina's Yellow. I had expected to see some gene segregation with the F2 plants, but didn't after planting out 12 plants in two different years.

So the predictions are statistical, and that's all they are.

Tell that to the mom who knows that the statistics say that there's a 50% chance of having a boy and she's given birth to 5 little girls in a row, as it were.



Is this a better way of saying this? Please don't hesitate to ask any questions and maybe I'll find even a better way of describing it.

[Tania]

Carolyn, stormymater, Gobig_or_Gohome_toms

thank you so much - you got me fixed!
It started to make sense for me again!

Tania

[carolyn137]

Originally Posted by Gobig_or_Gohome_toms

The 50/50 split would be the F2 generation plants, F1's would all have the same leaf type.

Go big, I didn't see your post when I quoted from Tania's above was half way though when a neighbor stopped by to return a book and we talked for about 30 min, I came back and finished my post and in the meantime you had posted clarifying, as I did, that we're talking about F2 saved seeds from an F1.

So I wasn't ignoring you, rather, you hadn't posted when I'd started doing my own post.

[Gobig_or_Gohome_toms]

Originally Posted by carolyn137

Go big, I didn't see your post when I quoted from Tania's above was half way though when a neighbor stopped by to return a book and we talked for about 30 min, I came back and finished my post and in the meantime you had posted clarifying, as I did, that we're talking about F2 saved seeds from an F1.

So I wasn't ignoring you, rather, you hadn't posted when I'd started doing my own post.

Not a problem at all.

[nctomatoman]

I will get a sense of my offtypes as I transplant...the seedlings are just showing true leaves. This is really one of the more interesting parts for me, when I can check on my seed saving skill/crossing percentage....esp. when looking at the PL varieties.

Also looking to see what my "poodle factor" is on Stick, and Variegation incidence on Variegated....with about 4000 tomato seedlings to examine, it is quite a data dump!

[kevokie]

I began potting up my little guys last night, and so far, have not found any off-types. I still have a long way to go, but so far so good.

[dice]

[Tania's question about all F1s being the same]

With F1 plants, if both parents were stable
OP (all homozygous gene pairs, either
CC or cc using the notation in the example
above), then you get what you described,
where every F1 plant is the same.

But if one of the parents was not a stable OP
(like a plant with the Cc heterozygous leaf type
gene pair in the example), then the gene pairs
in the offspring are not all the same. The not-stabilized
parent with the Cc gene pair could have contributed
either its C (RL) chromosome or its c (PL) chromosome
to any given seed. (50% of each in the next generation
offspring is only the probability; what you actually get
in a small number of seeds can vary from that.)

So, with seeds from an (F1 x stable OP) or
(F1 x different F1) cross, you get variations
in the next generation that fan out like plants
from F2 seeds.

[mtbigfish]

"Cc X Cc will give give you 3/4 PL and 1/4 RL"
Were you saying that C was dominant for PL in your genotype for leaf variety??

C and C or c give CC Cc
c and C or c give Cc cc
which gives you
3/4 PL and 1/4 RL
if C is dominant for PL or

3/4 RL and 1/4 PL if C is dominant for RL

or am I reading this wrong

Dennis

[carolyn137]

Originally Posted by mtbigfish

"Cc X Cc will give give you 3/4 PL and 1/4 RL"
Were you saying that C was dominant for PL in your genotype for leaf variety??

C and C or c give CC Cc
c and C or c give Cc cc
which gives you
3/4 PL and 1/4 RL
if C is dominant for PL or

3/4 RL and 1/4 PL if C is dominant for RL

or am I reading this wrong

Dennis

Dennis, I'm sorry, but I don't understand exactly what you copied and pasted above.

I think your question is about two heterozygotes crossing, which would be Cc X Cc

Above I listed all the possible crosses for almost all the genotypes and I also said that C is genetically dominant to c so the cross you ask about is:


C c

C CC Cc

c Cc cc


.......which gives 3/4 RL and 1/4 PL, as I said above.

OK, I went back up and see that I wrote the following:

Cc X Cc will give give you 3/4 PL and 1/4 RL

An error on my part, as I illustrated above it should be 3/4 RL and 1/4 PL

I got my PL's and RL's reversed. It happens!

Everything OK now?

[mtbigfish]

Yeah I thought it was but it's been 40+ years since I took Microbiology of the gene and wanted to make sure I didn't goof
Thanks I get my p's and q's mixed up sometimes too - or is that C and c or RL and PL ha ha - guess you were tired
Dennis

[b54red]

The Gary 'O Sena seed I got from you had a high percentage of RL with only one out of 4 being PL. I only planted 4 seeds on my first plant out and so I replanted in an attempt to get more true Gary 'O Senas. I am going to grow a couple of the regular leaf plants because they are the biggest healthiest looking plants of over 50 varieties I have potted up. I just hope they don't turn out to be cherries or some small tasteless tomato.

Originally Posted by Tania

Another offtype added to the list - Gerig. I got RL seedling instead of PL.

This brings it to:
24% of new to me PL varieties grown this year show some degree of crossing.

I am still waiting for the last LP to get the true leaves to get the final %-ages.


In a meantime, I am also checking my own PL seeds for purity - 2 batches of KBX, Brandywine Sudduth's, Orlov Yellow, and Aunt Gertie's Gold. 20-25 seeds planted in each batch, 100% seedlings are PLs. Still waiting for Gary'O Sena seeds to emerge...

Tania

[b54red]

You might want to try something that I have had great success with; using the bottom of egg cartons and only planting one seed per cup. The good thing is you can use the flap to label them and when you spoon them out you don't damage the root system. They are also very cheap and if you want you can take the top and use duck tape to close the holes on the side and use them for a water reservoir that the bottom can set in when it gets warm and you need to keep the water level higher.

Originally Posted by mensplace

Tatiana
Thanks for the sanity check! Noticed yesterday in my potting from seedlings of Jeff Davis that although I was very careful in organizing my seed rows with 1/2 inch between seeds in rows and an inch between the rows, there was a mix of those with RL and PL. In fact, as you noted, also saw this among other PL varieties. Does this mean that the actual fruits will not be, for instance, Jeff Davis, or simly that the plant with the RL simply carries a gene for a different leaf type? I saw this in so many PL varieties that I was seriously wondering how in the world I could have made such a mistake in seeding and was considering assigning the RL's to my UK (unknown) collection as they bore different leaves than what I knew they were "supposed" to be.

Next year I will be spacing my rows and individual seeds in the rows a bit further apart. I used the ESPOMA with organics and micro-organisms and the root systems are prodigious and I hate having to so damage the root mass by such close planting that I lose a considerable percentage of the roots when using and fork an some pulling apart to separate the individual plants.

[patty_b]

Not too many off types this time and a couple that i am not sure if they should be RL or PL.
Justine Heart 2 seeds planted 1RL 1PL
Hunt Family Pink 2 seeds planted 2RL
Schmatzfien 3 seeds planted 1PL 2RL
Indiana Heirloom(this one puzzles me) I saved the RL's last year because I liked it better than the PL's...planted 2 seeds and have 1 PL??

I looked at my Mrs. Benson seedlings and said oh no, they all PL's than OH yes...they are suppose to be PL's!!
Nicholaeva PL
ABC PL PL
Orlov Yellow PL
Hillbilly PL PL
English Rose too soon to tell but should be PL
Elbe no show